Over several centuries kites and airfoils have been constructed and utilized for different purposes. Uses of these kites and airfoils have included children's toys, games, objects of art, scientific research instruments, rescue devices and machines of war. Some of the basic characteristics of kites and airfoils, exploited in these applications, were their capability of high-altitude flight, their manoeuverability, and their capacity to lift large weights. Different design configurations of kites and airfoils were developed to better fulfill the requirements for these various utilizations but the principal benefit of such kites and airfoils was mostly derived from what they could do once they were airborne.
However, one characteristic of great interest in airfoils and kites is their ability to be made to be airborne to begin with. This characteristic illustrates and verify a principle of physics: the airfoil principle.
Kites and airfoils according to the present invention are designed so that the possibilities of observing the process by which the kite or airfoil is made airborne are maximized. Each time a gust of wind appears, the kite or airfoil rises automatically up a fixed pole, without further direct intervention. When the airflow or wind abates, the kite or airfoil descends the pole, and remains lowered until the next gust of wind or an increase in the airflow lifts the kite or airfoil up again, and so on. The restriction of the pole also keeps the kite or airfoil within a short distance of the observer who can have a closer and better view of the process of ascension of the kite or airfoil up the pole.
The applications of this invention include scientific instruments--with meters to count wind gusts and the rate of lift occurences each time the kite or airfoil ascends or descends the pole and instruments measuring the force of the lift, children's toys and advertising devices. The advertising application of the pole-restrained kite or airfoil is derived from the fact that the ascending and descending movements of such kite or airfoil devices, when they are placed in a public location, catch the eye and draw the attention to whatever message is displayed on the kite or airfoil or on the structure on top of which or near which the device is placed.
The pole-restrained kite or airfoil according to the invention comprises a kite or airfoil of any adequate and known design and to which may be attached any decorative element, a pole--not necessarily erected in a perfectly vertical position and which may be mobile--which passes through the body of the kite or airfoil, a restraining device which prevents the kite or airfoil from flying off the pole, a blocking device at the lower part of the pole which prevents the kite or airfoil to descend to the very bottom of the pole. The purpose of the latter device is to make it possible for the air masses of the wind or airflow to come under the kite or airfoil, whenever they are present, and lift such kite or airfoil; otherwise, if the kite or airfoil were allowed to drop to the very bottom of the pole, the airflow would only flow over the kite or airfoil and not under it and therefore would not provide it any lift.
One primary object of the invention is a kite or airfoil restrained by the radio antenna of an automobile. Each time the automobile begins to move the kite or airfoil rises up the antenna. Each time the car slows down, to stop at a red light, for example, the kite or airfoil descends the antenna and rests on the lower restraining device. The purposes of such an application include a toy to amuse children watching from inside the car and a moving sign/advertising device for car owners who want to attract attention to the message written on the kite or airfoil (a movable bumper-sticker of sorts).
This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.